Siemens 5SN6440-7CP 4-Pole MCB, 400V AC, 6kA EN 60898

The Siemens 5SN6440-7CP is a 4-pole miniature circuit breaker from the SENTRON 5SN family, designed for DIN-rail mounting in distribution boards and control panels. Its primary job is overcurrent protection of branch circuits — wiring, busbars, connected loads — in residential, commercial, and light-industrial installations. Rated 400 V AC at 50 Hz, it handles both multi-phase and single-phase operation up to 440 V AC maximum. The 6 kA breaking capacity per EN 60898 covers most domestic and commercial fault levels; the higher 10 kA rating per IEC 60947-2 gives headroom for industrial panels where the prospective short-circuit current is stiffer. That dual rating means the same part satisfies both the wiring regulation standard (EN 60898) and the industrial switchgear standard (IEC 60947-2) — one SKU for both compliance paths. Four poles let it switch all three phases plus neutral in a single unit — typical for 3P+N distribution. The 4-module-wide footprint (72 mm) and 70 mm installation depth fit standard SENTRON comb bars and busbar systems. Terminal capacity accepts up to 35 mm² solid conductor, sized for the feed side of a sub-distribution board.